<!DOCTYPE html>
<html>
<head>
  <title>Mapping Selectable Fields of Records</title>
  <meta name="description" content="Support selecting items inside nodes." />
  <!-- Copyright 1998-2016 by Northwoods Software Corporation. -->
  <meta charset="UTF-8">
  <script src="go.js"></script>
  <link href="../assets/css/goSamples.css" rel="stylesheet" type="text/css" />  <!-- you don't need to use this -->
  <script src="goSamples.js"></script>  <!-- this is only for the GoJS Samples framework -->
  <script id="code">
    function init() {
      if (window.goSamples) goSamples();  // init for these samples -- you don't need to call this
      var $ = go.GraphObject.make;  // for conciseness in defining templates

      myDiagram =
        $(go.Diagram, "myDiagramDiv",
          {
            initialContentAlignment: go.Spot.Center,
            validCycle: go.Diagram.CycleNotDirected,  // don't allow loops
            // For this sample, automatically show the state of the diagram's model on the page
            "ModelChanged": function(e) {
              if (e.isTransactionFinished) showModel();
            },
            "undoManager.isEnabled": true
          });

      // This template is a Panel that is used to represent each item in a Panel.itemArray.
      // The Panel is data bound to the item object.
      var fieldTemplate =
        $(go.Panel, "TableRow",  // this Panel is a row in the containing Table
          new go.Binding("portId", "name"),  // this Panel is a "port"
          {
            background: "transparent",  // so this port's background can be picked by the mouse
            fromSpot: go.Spot.LeftRightSides,  // links only go from the right side to the left side
            toSpot: go.Spot.LeftRightSides,
            // allow drawing links from or to this port:
            fromLinkable: true, toLinkable: true
          },
          { // allow the user to select items -- the background color indicates whether "selected"
            //?? maybe this should be more sophisticated than simple toggling of selection
            click: function(e, item) {
              // assume "transparent" means not "selected", for items
              var oldskips = item.diagram.skipsUndoManager;
              item.diagram.skipsUndoManager = true;
              if (item.background === "transparent") {
                item.background = "dodgerblue";
              } else {
                item.background = "transparent";
              }
              item.diagram.skipsUndoManager = oldskips;
            }
          },
          $(go.Shape,
            { width: 12, height: 12, column: 0, strokeWidth: 2, margin: 4,
              // but disallow drawing links from or to this shape:
              fromLinkable: false, toLinkable: false },
            new go.Binding("figure", "figure"),
            new go.Binding("fill", "color")),
          $(go.TextBlock,
            { margin: new go.Margin(0, 2), column: 1, font: "bold 13px sans-serif",
              // and disallow drawing links from or to this text:
              fromLinkable: false, toLinkable: false },
            new go.Binding("text", "name")),
          $(go.TextBlock,
            { margin: new go.Margin(0, 2), column: 2, font: "13px sans-serif" },
            new go.Binding("text", "info"))
        );

      // This template represents a whole "record".
      myDiagram.nodeTemplate =
        $(go.Node, "Auto",
          new go.Binding("location", "loc", go.Point.parse).makeTwoWay(go.Point.stringify),
          // this rectangular shape surrounds the content of the node
          $(go.Shape,
            { fill: "#EEEEEE" }),
          // the content consists of a header and a list of items
          $(go.Panel, "Vertical",
            // this is the header for the whole node
            $(go.Panel, "Auto",
              { stretch: go.GraphObject.Horizontal },  // as wide as the whole node
              $(go.Shape,
                { fill: "#1570A6", stroke: null }),
              $(go.TextBlock,
                {
                  alignment: go.Spot.Center,
                  margin: 3,
                  stroke: "white",
                  textAlign: "center",
                  font: "bold 12pt sans-serif"
                },
                new go.Binding("text", "key"))),
            // this Panel holds a Panel for each item object in the itemArray;
            // each item Panel is defined by the itemTemplate to be a TableRow in this Table
            $(go.Panel, "Table",
              {
                name: "TABLE",
                padding: 2,
                minSize: new go.Size(100, 10),
                defaultStretch: go.GraphObject.Horizontal,
                itemTemplate: fieldTemplate
              },
              new go.Binding("itemArray", "fields")
            )  // end Table Panel of items
          )  // end Vertical Panel
        );  // end Node

      myDiagram.linkTemplate =
        $(go.Link,
          { relinkableFrom: true, relinkableTo: true, toShortLength: 4 },  // let user reconnect links
          $(go.Shape, { strokeWidth: 1.5 }),
          $(go.Shape, { toArrow: "Standard", stroke: null })
        );

      myDiagram.model =
        $(go.GraphLinksModel,
          {
            linkFromPortIdProperty: "fromPort",
            linkToPortIdProperty: "toPort",
            nodeDataArray: [
              { key: "Record1",
                fields: [
                  { name: "field1", info: "", color: "#F7B84B", figure: "Ellipse" },
                  { name: "field2", info: "the second one", color: "#F25022", figure: "Ellipse" },
                  { name: "fieldThree", info: "3rd", color: "#00BCF2" }
                ],
                loc: "0 0" },
              { key: "Record2",
                fields: [
                  { name: "fieldA", info: "",       color: "#FFB900", figure: "Diamond" },
                  { name: "fieldB", info: "",       color: "#F25022", figure: "Rectangle" },
                  { name: "fieldC", info: "",       color: "#7FBA00", figure: "Diamond" },
                  { name: "fieldD", info: "fourth", color: "#00BCF2",  figure: "Rectangle" }
                ],
                loc: "250 0" }
            ],
            linkDataArray: [
              { from: "Record1", fromPort: "field1", to: "Record2", toPort: "fieldA" },
              { from: "Record1", fromPort: "field2", to: "Record2", toPort: "fieldD" },
              { from: "Record1", fromPort: "fieldThree", to: "Record2", toPort: "fieldB" }
            ]
          });

      // this is a bit inefficient, but should be OK for normal-sized graphs with reasonable numbers of items per node
      function findAllSelectedItems() {
        var items = [];
        for (var nit = myDiagram.nodes; nit.next(); ) {
          var node = nit.value;
          var table = node.findObject("TABLE");
          if (table) {
            for (var iit = table.elements; iit.next(); ) {
              var itempanel = iit.value;
              if (itempanel.background !== "transparent") items.push(itempanel);
            }
          }
        }
        return items;
      }

      // Override the standard CommandHandler deleteSelection behavior.
      // If there are any selected items, delete them instead of deleting any selected nodes or links.
      myDiagram.commandHandler.canDeleteSelection = function() {
        // true if there are any selected deletable nodes or links,
        // or if there are any selected items within nodes
        return go.CommandHandler.prototype.canDeleteSelection.call(myDiagram.commandHandler) ||
               findAllSelectedItems().length > 0;
      };

      myDiagram.commandHandler.deleteSelection = function() {
        var items = findAllSelectedItems();
        if (items.length > 0) {  // if there are any selected items, delete them
          myDiagram.startTransaction("delete items");
          for (var i = 0; i < items.length; i++) {
            var panel = items[i];
            var nodedata = panel.part.data;
            var itemarray = nodedata.fields;
            var itemdata = panel.data;
            var itemindex = itemarray.indexOf(itemdata);
            myDiagram.model.removeArrayItem(itemarray, itemindex);
          }
          myDiagram.commitTransaction("delete items");
        } else {  // otherwise just delete nodes and/or links, as usual
          go.CommandHandler.prototype.deleteSelection.call(myDiagram.commandHandler);
        }
      };

      showModel();  // show the diagram's initial model

      function showModel() {
        document.getElementById("mySavedModel").textContent = myDiagram.model.toJson();
      }
    }
  </script>
</head>
<body onload="init()">
<div id="sample">
  <h3>Mapping Fields of Records</h3>
  <p>This shows a variable number of selectable "fields" for each "record".</p>
  <p>Draw new links by dragging from the background of any field.
     Reconnect a selected link by dragging its diamond-shaped handle.
     The user can delete a selected field.</p>
  <div id="myDiagramDiv" style="border: solid 1px black; width:100%; height:300px"></div>
  <p>The model data, automatically updated after each change or undo or redo:</p>
  <textarea id="mySavedModel" style="width:100%;height:300px"></textarea>
  <p>This sample was derived from the <a href="records.html">Records</a> sample.</p>
</div>
</body>
</html>